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  1. Replies
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    10,150

    Yes but if you intend to hold the glass in place...

    Yes but if you intend to hold the glass in place with just one hand, the location will be one third up from the bottom, with a force equal to the average pressure times area.

    In the hypothetical...
  2. Yes you can run it on 3 phase. Wire the motor...

    Yes you can run it on 3 phase.

    Wire the motor for 240v (two 120v coils in series).

    Connect the capacitor start winding to the midpoint of the main coils, and the third phase of the vfd.

    Turn...
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    497

    You ask the weirdest questions. Good idea for...

    You ask the weirdest questions.

    Good idea for a drill press vise.
  4. Replies
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    6,572

    grind or scrape bars that fit the gap in the ways...

    grind or scrape bars that fit the gap in the ways as best you can, leaving the surface flat but the back side rough. intentionally rough. or saw cut lots of grooves in it.


    use .005" shims and...
  5. Replies
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    2,240

    find some motor run caps, 10-50uf will work....

    find some motor run caps, 10-50uf will work. delta, or y connection doesn't matter. values not critical. 10uf will be enough if you have 4khz or higher pwm frequency. larger caps can be connected in...
  6. Replies
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    2,119

    this has been discussed before and it appears to...

    this has been discussed before and it appears to be a myth. the photo that is always used in those articles shows a cast iron lathe bed which used a steel rod as the "way"


    anyhow regarding rail...
  7. 291339 So just to be clear, if you completely...

    291339

    So just to be clear, if you completely screw up cutting the dovetail on a wedge type tool post and have to add back 1/8" of steel... That is the surface im talking about. In the photo i...
  8. Rather that open up the dovetail by .001 to .003"...

    Rather that open up the dovetail by .001 to .003" (which requires careful set up to keep it parallel and square, you can take a couple thousanths off the whole flat face of the dovetail.
  9. Replies
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    1,396

    i've used 7" wire wheels rated for 4500 rpm on my...

    i've used 7" wire wheels rated for 4500 rpm on my 4.5" angle grinder. the air drag loads it down and its a bit scary to use but, they hold up just fine.

    no way would i put a 14" wheel on a 9"...
  10. Replies
    4
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    750

    motors buzz because the core is saturated and the...

    motors buzz because the core is saturated and the magnetic field is escaping the stator core and causing the rest of the motor casing to vibrate.. typically sheet metal.
  11. grind the circlip groove with one of those dirt...

    grind the circlip groove with one of those dirt cheap .040" thick 100mm angle grinder cut off blades for angle grinders. the groove will be mostly circular profile at the root of it which should not...
  12. Replies
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    750

    remove some of the run capacitors until you see...

    remove some of the run capacitors until you see that 250 volt number drop a bit, or just ignore it. 250 volts no load is not too high.

    you can then take those capacitors which were removed and...
  13. cavitation is also influenced by the gas pulled...

    cavitation is also influenced by the gas pulled out of the fluid on the suction side of the pump. if the gas does not get pushed downstream it flows around the impeller through the seals. or lack of...
  14. Replies
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    1,396

    the motor you have is probably repairable if you...

    the motor you have is probably repairable if you are willing to carefully examine the copper connection between the commutator and the coils. i'm suspecting fatigue failure.

    i repaired the motor...
  15. either you are single phasing the motor or you...

    either you are single phasing the motor or you have a volts per hz curve that is wildly incorrect.

    i can think of no reason why you would see more than nameplate full load amps for your lathe, as...
  16. Replies
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    2,240

    Did you add delta caps after the load reactor?

    Did you add delta caps after the load reactor?
  17. Replies
    56
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    3,246

    Its not kosher but you can flush the air out of...

    Its not kosher but you can flush the air out of the lineset and indoor minisplit unit with the refridgerant. The instructions on how to do it are printed in the hieroglyphic instruction manual. No...
  18. Replies
    23
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    2,240

    you could use a 9 wire motor as a 3 phase line...

    you could use a 9 wire motor as a 3 phase line reactor. lock the rotor so it doesn't spin up. the y connected coils would be disconnected and the other 3 coils used.

    the impedance will be on the...
  19. Replies
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    2,224

    the pure sine wave filter should be a special...

    the pure sine wave filter should be a special core that has a very high common mode inductance to filter out the common mode voltage, which is what destroys motor bearings.
    for example: Sine Wave...
  20. Replies
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    2,224

    Had some corespondance with a man who tried a...

    Had some corespondance with a man who tried a cheap automation direct line load reactor for the sine wave filter applications i have spoke of, and while it worked it got very hot. He found the...
  21. Replies
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    2,224

    I got away with as little as 500uH for a 400watt...

    I got away with as little as 500uH for a 400watt 240v vfd. (A 9mh 3 phase line load reactor had only 480uH common mode inductance)


    I found that 65 feet of 12/3 wire coiled up as tightly as i...
  22. Replies
    19
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    2,224

    That filter seems suspicious to me. It is...

    That filter seems suspicious to me. It is probably a CLC configuration for noise removal.

    Go to home desperate and buy 3, 500 foot spools of 12 guage wire and you've got 3 inductors. Any ordinary...
  23. Replies
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    2,240

    I explained in my post on the other thread before...

    I explained in my post on the other thread before i saw this one.
  24. You probably need to pull the end plate off (its...

    You probably need to pull the end plate off (its staked in 3 places) to braze the ring together.

    The keys have a spring wrapped around them and once some rpm is reached they fly outward and touch...
  25. Replies
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    2,224

    Cheapest method will be a 480v vfd with a line...

    Cheapest method will be a 480v vfd with a line load filter on the output and delta connected capacitors to clean up the waveform. Collectively all 3 phases will still have a square wave of 340volts...
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